Hello and welcome to NewsHour from the BBC World Service coming to you live from London. I'm Paul Henley.

A significant conflict in the Middle East seems to be on the verge of dramatic escalation. The head of Iran's

Revolutionary Guard, Hossein Salami, is today warning of devastating retaliation if President Trump carries out a threat to hold Iran responsible

for Houthi attacks on shipping in the Red Sea.

Iran will not wage war, but if anyone threatens,

it will give appropriate, decisive and conclusive responses.

Ansar Allah of the Houthis, the representatives of the Yemenis,

makes its own strategic and operational decisions.

The Houthis are a Shia Islamic military and political movement

and they are a central player in Yemen's ongoing civil war.

They frequently targeted international shipping in support,

they say, of Palestinians in the Israel-Hamas war, although their attacks were largely paused

during the Gaza ceasefire agreement. The Iranian authorities say the US has failed to learn the lesson

that war is not a solution to its problems. But President Trump has renewed his warning to

Iran, saying the US will hold Iran fully accountable for the actions of the Houthis, adding,

we won't be nice about it. Mr. Trump issued his threats as US forces launched large-scale

strikes against Houthi targets. The strikes are thought to have killed 30 people,

and they're the biggest US military operation since he returned to office. This is audio from

footage posted on social media by the US Central Command yesterday as fighter jets took off. Radia al-Mut-Wakal is a human rights activist based in the Yemeni capital, Sanna.

She told the BBC people there were now living in fear.

We are all worried.

We forgot how these, I mean, explosions and this kind of fear felt.

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